SUMMARY OF THE INVENTION Accordingly, one object of the present invention is to provide a method for reactivating poisoned Raney nickel catalysts.

Briefly, this object and other objects of the invention as.,hereinafter will become more readily apparent can beattained by providing a method for the reactivation of a poisoned Raney nickel catalyst used for the hydrogenolysis of an organic peroxide polymer by treating the catalyst with a 0.1 N solution of an activating reagent selected from the group consisting of ammonia, an alkali metal or an alkaline earth'metal hydroxide, carbonate or carboxylate having 1-4 carbon atoms at 2 0-200C under an inert gas atmosphere.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS:

The poisoned Raney nickel catalysts to which'the process of the present invention is applicable include Raney nickel catalyst which are modified by small amounts of copper, chromium, iron, or the like which are used in the hydrogenolysis of organic peroxide polymers. The organic peroxide polymers which are subjected to hydrogenolysis include peroxide polymers of olefins which include conjugated diolefins such as butadiene, isoprene, 2-ethyll 3-butadiene, 2 ,3-dimethyl-l ,3-butadiene, 2,5-dimethyl-2,4- hexadiene, alkyl substituted conjugated diolefins thereof; cyclo substituted conjugated diolefins such as cyclopentadiene, cyclohexadiene, dimethylfuran, furan; alkyl substituted cycle conjugated diolefins, and indene and styrene.

It has been found that organic peroxide polymers can be subjected to hydrogenolysis in the presence of a contact between the catalyst and the polymer,'-the catalyst is suspended in a medium and then exposed'to a hydrogen atmosphere whereby the hydrogen is absorbed. At the same time theorganic peroxide polymer is added to the medium which of course dilutes it, through a high pressure, small amount constant volume pump, at a rate the same or less than the rate of hydrogenolysis of the polymer. In the hydrogenolysis reaction, however, poisoning materials such as organic acids, polymers and the like continue to be absorbed on the surface of the catalyst which in turn decreases the amount of active surface area of the catalyst and results in a rapid decrease in activity even though the contact method improves the reaction. Thus, the amount of the organic peroxide polymer which can be hydrogenated perunitamount of the Raney nickel catalyst is limited and of course,- it is. consumed as the reaction proceeds.

An-investigation into the problem of the deactivation. of the catalyst has revealed thatRaney nickel catalysts poisoned by organic peroxide polymers can ,be reactivated by treating the inactivated catalyst with a solution of an activating reagent such as ammonia, an alkali metal or an alkaline earth metal hydroxide carbonate or carboxylate having l-4 carbon atoms under an inert gas atmosphere after each hydrogenolyis reaction. This method of reactivation of a poisoned Raney nickel catalyst which is presently used in the hydrogenolysis of organic peroxide polymers has heretofore been unknown. When the procedure is repeatedly used to remove the poison from the catalyst, the catalyst can be reused from 50 to 100 times.

In the reactivation of Raney nickel, the temperature at which the catalyst is treated, the concentration of the activating reagent and the treatment time all influence the degree of activation. The treatment temperature usually ranges from 20 to 200C, preferably 50 to 120C, especially 70 to 120C. If the treatment temperature is greater than 200C the aluminum component of the Raney nickel catalyst is dissolved and consequently the nickel atoms are rearranged. Also, the

crystalline particles are increased and the catalytic activity is decreased. From the viewpoint of catalyst life, it is preferably that the temperature be lower. However, at temperatures less than 20C, the separation of the absorbed poison from the Raney nickel catalyst is too slow and the treatment time is too long. Suitable media for the activating reagents include water, and lower alcohols such as methanol, ethanol'and isopropanol. Satisfactory treatment results are also achieved when the concentration of the activating reagent Raney nickel catalyst. However the organic peroxide hydrogenation reaction. In order to improve the ranges from 0.1 to 5 N.

The treatment time depends upon the concentration of the activating reagent, the treatment temperatures and the ratio of the organic peroxide polymer to the Raney nickel catalyst in the hydrogenolysis reaction and is usually 2 to 8 hours. The treatment conditions for the Raney nickel catalyst depend upon the ratio of the organic peroxide polymer to the Raney nickel, which must be severe at increased ratios. From the viewpoint of catalyst life, severe treatment times are preferably used rather than using increased treatment temperatures. Suitable inert gases which can be used in the treatment of the poisoned Raney nickel catalyst include hydrogen, nitrogen and the like. These gases do not adversely effect the activity of the catalyst, and preferably hydrogen is used.

Having generally described this invention, a further understanding can be obtained by reference to certain specific examples which are provided herein for pur posesof illustration only and are not intended to be limiting unless otherwise specified.

The total yield of the diols based on thej soprene peroxide polymer was 45.7%. The poisoned Raney nickel catalyst and 100 cc of an aqueous 0.5 N-NaOl-Isolution were charged into the 200 cc autoclave equipped with an electromagnetic stirrer, and the mixture was heated and stirred at 90C for 3 hours under a hydrogen atmosphere to activate the catalyst. The .catalyst was sepa-.

rated, and thereafter wasused for the hydrogenolysis of the isoprene peroxide polymer. The operation was repeated 30 times with the same catalyst, and no decrease inactivity of the catalyst was not found.

EXAMPLES 2 10 In the autoclave of Example 1, each of the peroxide polymers shown in Table 1 were hydrogenated under the reaction conditions shown in Table 1. After each hydrogenolysis reaction, the poisoned Raney nickel catalyst was treated under the conditions shown in Table 1. This cycle was repeated a number of times as shown in each Example in the table. The results are shown in Table 1.

Theyield of 1,4-butanediol based on the butadiene peroxide polymer was 56%. The poisoned Raney nickel catalyst and 100 cc of an aqueous 0.5 N-NaOH'solution were charged into the 200 cc autoclave equipped with an electromagnetic stirrer, and the mixtu re was heated and stirred at 90C for 3 hours under a hydrogen atmosphere to activate the catalyst. The catalyst was separated and was used for the hydrogenolysis of isoprene peroxide polymer.

,The operation'was repeated 100 times using the same catalyst, and no decrease in activity of the catalyst was found.

Having now fully described this invention, it will be apparent to one of ordinary skill in the art that many changes and modifications can be made thereto without departing from the spirit or scope of the invention as set forth herein.

' What is claimed as new and intended to be covered by Letters Patent is:

1. A method for the reactivation of a poisoned Raney nickel catalyst modified by a small amount of metal from the group consisting of copper, chromium and iron which is used for. the hydrogenolysis of inorganic peroxide polymer to form a diol product which comprises treating said catalyst with a 0.1 N aqueous or lower alcohol solution of an activating reagent selected from the group consisting of ammonia, an alkaline earth m etal. hydroxide.- carbonate or carboxylate having 1 4 carbon atoms'and an'alkali metal carbonate or carboxylate having from 1 4 carbon atoms at 2020( )C underan atmosphere of hydrogen or nitrogen from 2 to 8 hours, and separating said treated catalyst from said aqueous or lower alcohol solution.

4. The method of claim 1, wherein the organic peroxide polymer is an olefin peroxide polymer of an olefin selected from the group consisting I, of isoprene, 2,5 dimethyl-2A-hexadiene; 2,3-dimethyl- 2,3-butadiene cyclopentadiene and styrene. L Y

5. The method of claim 1, wherein said solution of the activating reagent is prepared from water.

9. The method of claim 1, wherein said activatingreagent is an alkaline earth metal carbonate. 10. The method of claim 1, wherein said activating reagent is an alkaline earth metal carboxylate having from 1 to 4 carbon atoms.

I 2-ethyl-l ,3-butadiene,

r UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION PATENT NO. 2 3,896,051 DATED duty 22, 1975 |NvENTOR(S) Shunsuke Mabuchi et a] It is certifi ed that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:

Column 7, Iine 26 (Claim 1, line 4) change "inorganic" to an organic Signed and Scaled this T t-f rth a I {SEAL} weny out D y 0f August 1976 Arrest: